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# Please Explain How Fractal Wood Burning Patterns are produced by DC Electricity

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Here are 3 typical videos of fractal wood burning: video 1, video 2 and video 3.

As can be seen in all the videos, the different Lichtenberg figures develop simultaneously from both the positive and negative electrodes as the electric current follows leader lines within the wood that represent the pathways of least resistance. However, due to the high resistance of the wood, it heats up and burns to form carbon, which is a good conductor, and which allows the burning to move outwards from the electrodes. Multiple burn paths quickly develop and simultaneously expand from each electrode to produce quite stunning and unique Lichtenberg figures.

When I first come across these impressive wood burning examples, I thought that it was due to the application of AC electricity. But no, in fact a high voltage (about 2000 volts), high amperage DC current is used.

Surely, with DC electric current consisting of the one-way movement of electrons, a single Lichtenberg figure should be expected to grow from negative electrode and expand towards the positive electrode. So, exactly why do Lichtenberg figures develop simultaneously from each electrode if the burning is caused by electrons moving from the negative electrode to the positive electrode? Can anyone provide a reasonable and convincing explanation of why this is the case?

And, yes, the Lichtenberg figures are not true fractals, so let’s not waste time on that subject.

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After 40 or so views and no answer to this perplexing question, we can assume that nobody has a ready feasible answer, and so I will endeavour to give the topic a nudge.

The development of Lichtenberg figures from the negative electrode is readily explained in terms of the negative charge carriers (i.e. electrons) being forced into the wood by high voltage which, due to the high resistance, generates heat that causes wood to burn.  However, it would appear that a similar process is occurring at the positive electrode, but herein lies the problem: the only charge build-up there would be in terms of positive holes which, for those static cations that are called positive holes, is essentially an energy-reduction process. So, why would there be a similar burn process at the positive electrode?

Another possibility is that there are positron-like positive charge carriers being pushed into the wood at the positive electrode which generates a burn effect similar to that generated by the electrons (or negative charge carriers). This would be a simpler explanation, but raises a host of other issues.

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• 2 weeks later...

It is not really perplexing; have you never heard of convention current flow?

It make no difference to the analysis whether you use electron current flow or conventional current.

This forum does not encourage the practice of using electric current to burn patterns in wood ; too many people have died from attempting this.

It is a very dangerous procedure and this forum is now on record as being against this, so you will not be receiving any further responses.

Edited by OceanBreeze